Knowing what RDFA vocabulary to use

There are many vocabularies. And you could create your own, too, of course (but you probably shouldn’t before you checked possible alternatives). You’d have to look for vocabularies for your specific needs, for example by browsing and searching on http://lov.okfn.org/dataset/lov/ (they collect and index open vocabularies), on W3C’s RDFa Core Initial Context (it lists vocabularies … Read more

How can I express additional information (time, probability) about a relation in RDF?

There are several options to do this. I’ll illustrate some of the more popular ones. Named Graphs / Quads In RDF, named graphs are subsets of an RDF dataset that are assigned a specific identifier (the “graph name”). In most RDF databases, this is implemented by adding a fourth element to the RDF triple, turning … Read more

Microdata vs RDFa

Differences between Microdata and RDFa While there are many (technical, smaller) differences, here’s a selection of those I consider important (used my answer on Webmasters as a base). Specifications As W3C’s HTML WG found no volunteer to edit the Microdata specification, it is now merely a W3C Group Note (see history), which means that there … Read more